Chair base and method of making the same



June 7, 1938. R; w BANCRQFT 2,119,946

cmun mass AND mmnon OF MAKING THE SAME Filed Feb. 28, 1956 JW W W Patented June 7, 1938 UNITED STATES PATENT series Raymond W. Bancroft, Gardner, Mass, assignor to Collier-Keyworth Company, Gardner, Mass, a corporation of Massachusetts Application February 28, 1936, Serial, No. 66,146

Claims.

This invention relates to chair bases more part cularly for swivel chairs. A base of this type is commonly provided with a central hub portion centrally apertured to adjustably receive the lower portion of a seat-supporting spindle, this hub portion being held elevated above the floor by a plurality of radially arranged legs, the outer ends of which-are supported from the floor. The weight of the chair and its occupant thus exerts great pressure tending to spread the legs, tending to pull them away from the hub at their lower portions, and this pressure acts on the securement of the legs on the hub portion through the effectively long lever arms extending to the outer end portions of the legs.

One of the objects of this present invention is to provide a construction wherein this severe stress is directed to securing parts of great strength amply able to take it.

A further object is to provide such a strong and simple construction which is simple and cheap to make.

A further object is to produce a construction of good appearance.

Further objects and advantages will appear from a more complete description of an embodiment of this invention shown in the accompanying drawing in which Figure 1 is a fragmentary perspective view of a chair having a base constructed in accordance with this invention.

Figure 2 is a perspective view of a metal cover plate for the lower end of the base hub.

Figure 3 is an exploded inverted perspective showing the legs and corner pieces separated preparatory to assembling.

Figure 4 is a fragmentary perspective view showing the parts of Figure 3 assembled and prepared to receive the securing ring shown separated therefrom.

Figure 5 is a detail vertical section through the hub and one leg of the assembled base in inverted position.

Referring to the drawing at I are shown leg members, four being illustrated, which radiate from a common center. These leg members are held spaced in the desired angular relationship by corner blocks 2, each corner block being positioned between two adjacent legs I. As shown the inner ends of the leg portions are of reduced width as at 3 forming shoulders 4 which take over the outer edges of the blocks 2 and hold the blocks from end toend in proper relation to the legs I. These blocks 2 are each of a length substantially equal to the depth of the leg members so that when they are fitted together they 1 form with the leg members a hub portion 5.-

These leg members preferably do not extend inwardly into contact with each other, being spaced apart as shown in Figure 4 to provide a central driven into position so as to be embedded in the hub portion of the base, as shown in Figure 5, this ring member It being substantially concentric with the hub portion and with the center from which the leg members I radiate. The top face of the hub may be covered by a metal plate I2 which is shown as provided with a tubular extension I3 and the hub tube ill to slidingly receive the chair spindle l and it may be provided with means (not shown) of any suitable or usual form to adjustably engage the spindle so that the height of the chair seat I5 may be adjusted as desired while permitting rotation of the spindle within the hub in the well known manner. This plate I2 which may be substantially co-terminous with the hub portion of the base between the legs I may be secured as by screws I8.

The lower face of the hub portion is covered by a metal plate provided with a central aperture 2! through which the hub tube II! may extend, this plate having apertured cars 22 spaced to correspond with the spacing of the leg members I and as shown bent out of the plane of the central portion of the plate 20 to conform to the contours of the leg members I adjacent to the central hub portion of the base. This plate 20 is shown as provided with screw-receiving holes 23 for screws 24 which penetrate into the leg members I within the hub portion of the base.

Apertures 25 in the ears 22. receive screws 26 which penetrate into the leg members I outwardly of the hub portion of the base. It will be noted that the ring member Ill which ties the leg members together and to the filler blocks 2 is embedded in the hub portion and is entirely out of sight in the finished base. It takes the very severe stresses which would tend to separate the lower portions of the leg portions from the hub, these stresses arising from the weight of the chair and its occupant and relieves the screws 24 and 26 from this service. Without the ring member ID, as formerly constructed, all these stresses are taken by the screws which secure the end plates in position and-these are ill adapted to take anysuch severe stresses. The side portions of the hub member thus present the surfaces of the leg members and filler blocks, both of which may be of wood, and permit a uniform and pleasing finish forthe exterior of the chair base. tirely free from any attaching means or metal parts, all the metal parts which show being the end cover plates for the hub part of the base.

From the foregoing description of an embodiment of this invention, it should be evident that various changes and modifications might be made without departing from the spirit or scope of the invention as defined by the appended claims. 7

I claim:

1. A chair base comprising a plurality of leg members radiating from a common center, filler blocks each having inner angularly related faces positioned between the inner ends of the adjacent leg members and holding said members in 'gangular relation and together therewith forming a hub portion, said blocks each being of a length substantially the depth of said members, said base-having a continuous annular channel in one end of each of said blocks and across said members and substantially concentric with said center,'a metal ringseated in said channel and holding said members and blocks in assembled relation, and plate elements secured to the faces of said hub portion.

These surfaces of the base are enleg members and holding said members in angular relation, and an annular member substantially concentric with said center embedded in said blocks and leg members and retaining them in assembled relation.

3. A chair base comprising a plurality of leg members radiating from a common center, blocks each having inner angularly related faces positioned between the inner ends of the adjacent lar relation and forming a hub therewith, an annular member substantially concentric with said.

center embedded in said blocks and. leg members and retaining them in assembled relation, and plates secured thereto over the ends of said hub.

4. The method of making a chair base, which comprises assembling a, plurality of leg members radiating from a common center and filler blocks each having inner angularly related faces between the inner ends of said leg members, and While said blocks and members are held assembled, cutting an annular slot intersecting said members and blocks, and then forcing a ring member into said slot.

5. The method of making a chair base, which comprises assembling a plurality of leg members radiating from a, common center and segmental filler blocks each having inner angularly:

related faces between the inner ends of said leg members to form a hub portion from which the outer ends of said members extend, and while said blocks and said members are so held, cutting an RAYMOND W. BANCROFT. 

